Method and system of reducing charged particle beam write time

Abstract

A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.

Description

BACKGROUND OF THE DISCLOSURE[0001]The present disclosure is related to lithography, and more particularly to the design and manufacture of a surface which may be a reticle, a wafer, or any other surface, using charged particle beam lithography.[0002]Three common types of charged particle beam lithography are unshaped (Gaussian) beam lithography, shaped charged particle beam lithography, and multi-beam lithography. In all types of charged particle beam lithography, charged particle beams shoot energy to a resist-coated surface to expose the resist.[0003]Shaped charged particle beam lithography may be variable shaped beam (VSB) or character projection (CP), in which a shot of a precise electron beam is shaped and steered so as to expose a resist-coated surface, such as the surface of a wafer or the surface of a reticle. In VSB, these shapes are simple shapes, usually limited to rectangles of certain minimum and maximum sizes and with sides which are parallel to the axes of a Cartesian...

AI Technical Summary

Benefits of technology

The patent describes methods and systems for creating patterns on surfaces using a charged particle beam. The system calculates the backscatter of the pattern and creates an artificial background dose, which is combined with the original exposure information to create a modified set that will be used to create the pattern. Overall, this allows for more precise and accurate pattern creation.

Problems solved by technology

An example of an end-use limitation is defining the geometry of a transistor in a way in which it cannot sufficiently operate at the required supply voltage.

The design rule limitations reflect, among other things, the smallest dimensions that can be reliably fabricated.

As the critical dimensions of the circuit pattern become smaller and approach the resolution value of the exposure tool, the accurate transcription of the physical design to the actual circuit pattern developed on the resist layer becomes difficult.

Narrow spaces are harder to write reliably than equally narrow lines, so these negative features often end up being the most difficult parts to write reliably on a surface.

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